Same fix as nxtgauge-frontend-solid: GITEOPS_REPO/GITEOPS_SSH_KEY were
never configured as repo secrets. Switch to an HTTPS clone with
GITOPS_PAT, matching nxtgauge-backend-rust's already-working workflow.
Same fix as nxtgauge-frontend-solid: buildx writes its metadata file
pretty-printed, so the compact ":"-only grep pattern never matched,
failing the build-and-push step right after a successful push and
skipping the GitOps-release step. Match backend-rust's
whitespace-tolerant pattern.
Same fix as nxtgauge-backend-rust and nxtgauge-frontend-solid: every
build here has been failing with "Cannot connect to the Docker daemon
at tcp://127.0.0.1:2375" since the job container is nested inside the
runner pod's dind sidecar. Detect the real gateway from
/proc/net/route instead of hardcoding loopback.
